Adhesive applying apparatus



June 18, 1946. I BAILEY 2,402,272

ADHESIVE APPLYING APPARATUS Filed Jan. 4, 1943 2 Sheets-Sheet 1 W. T. BAILEY ADHESIVE APPLYING APPARATUS June 18, 1946.

Filed Jan. 4; 1945 2 SheetS-Sheet 2 B AW ATTORNEY.

Patented June '18, 1946 ADHESIVE APPLYING APPARATUS Walter '1. Bailey, Philadelphia, Pa., assignor to Stokes and Smith Company, Philadelphia, Pa., a corporation of Pennsylvania Application January 4, 1943, Serial No. 471,268

16 Claims. (Cl; 91-49) 1 My invention relates to apparatus for applying adhesive to wrappers, labels, tabs, and the like. generically termed sheets, to be applied to stayed or unstayed boxes, and, in particular, concerns apparatus which effects adhesive attachment of-tabs to wrappers and coats the tabbed wrappers with adhesive for attaching them to boxes or the like.

In accordance with my invention, the usual open reservoir of adhesive, disposed beneath the adhesive applying roll or rolls and associated feeding and/or sheet-coating mechanism, and in which the adhesive is agitated by a roll which transports the adhesive therefrom more or less directly to the sheet applying rolls, is dispensed with in avoidance of disadvantages including foaming of the adhesive and of condensation of adhesive-bearing vapors upon the rolls and the feeding or coating mechanism. In substitution for such reservoir, the adhesive is supplied by a pump from a reservoir the space above whose contents is substantially isolated from the rolls and in which the adhesive is agitated by a paddle or equivalent structure which preferably remains below the surface of the adhesive and which is discharged to the pump from an outlet at or near the bottom of the reservoir.

Further in accordance with my invention, the adhesive is delivered by the pump to a valley formed by an adhesive applying roll and an associated scraper member extending lengthwise thereof, andthe excess of adhesive is collected at the ends of the valley by trough structure which directs it to a lower valley formed by a second roll and scraper arrangement.

My invention'further resides in features of construction and arrangement hereinafter discussed and in general is directed to improvedisclosed in Letters Patent 2,276,683 to Bailey, Letters Patent 2,028,878, 1,857,260, 1,806,181, to

Rider, Letters Patent 728,086 and 1,818,198 to.

' ments in adhesive-applying apparatus of thetype Davis, and in applications Serial Numbers 397,894

June 6, 1941 and February 12,

Fig. 2, in perspective, shows strainer structure comprised in apparatus of Fig. 1:

Fig. 3 is a sectional view of a slip-clutch or friction-drive device included in the mechanism of F1 .1;

Fig 4 is a side view, princip lly, on enlarged scale and in section, of parts appearing in Fig. 1;

Fig. 5 is a fragmentary plan view of rolls and trough structures shown in Figs. 1 and 4;

Fig. 8 is a fragmentary side-elevational view of roll and'scraper structure shown in Fig. 4;

Fig. 7 is a fragmentary end view of drip pan structure shown in Fig. 4.

Referring to Figs. 1 and 4, the roll I of the adhesive-applying machine co-operates with a scraper member or roll 4, preferably an intermittently operated doctor roll, to define a valley, Fig. 4, V into which adhesive is discharged from a pipe I preferably, extending above the valley to a point substantially removed from both ends of roll i and preferably, for uniformity of the coating upon roll I, provided with a plurality of perforations spaced lengthwise of the valley and through which the adhesive is discharged as a plurality of jets.

The surface of roll I in passing through the adhesive in valley V receives a thin uniform coating transferred to wrappers W fed to roll I by rolls 2 I and deflected therefrom as by knives 82 onto the conveyor "which transports them to a station not shown at which they are applied to stayed or unstayed boxes. The tabs cut from strips T depending upon their location serve to reinforce and/or stay corners of the box; the wrapper itself also serves to reinforce or stay the box-comers. V

The excess of adhesive supplied to the valley V flows towards the ends thereof and is collected by trough structures I each preferably of width suited to straddle the valley with the substantially vertical sides 1, 8 of the trough in engagement respectively with the ends ofrolls 4 and I. The two streams of adhesive collected by the troughs 4 flow downwardly and toward one another (Flg. 1) as directed by chutes 9, 9 of collector member 90.. Some of the adhesive escapes from the openings II in chutes l, I for discharge from the series oftroughs Ila spaced lengthwise of a second valley VI the-remainder of the adhesive reaches the common-spout I 2: thus the adhesive is. discharged from member a as a thin Wide stream (Fi 4) into the aforesaid second valley VI defined by the roll I3 an ciatedscraper member I4. when the frame or bridge 43 is swung away from the position shown in Fig. 4 to the position shown in Fig. 1, for

cleaning or inspection, the adhesive or cleansing liquid discharges from spout I2 directly into tray frames 38 of the machine G.

The roll I! transports or transfers adhesive form the lower valley VI to the roll I! which as now described applies adhesive to the faces of tabs destined to engage wrappers or sheets fed by roll 2 and 8 into engagement with roll I. As more fully disclosed and described in aforesaid patents, the tabs are cut from strips of sheet tabbing material by knives 44, respectively associated with two similar tabbing heads 45 adjustably supported by the frame of bridge member 43 for movement toward and from each other to suit the spacing between tab to wrappers of differentwidths; when tabs only are to be applied a different arrangement similar to that of aforesaid Davis Patent 728,086 is utilized. Reverting to Figs. 1 and 4 hereof, while the knives 44 are in their upper or retracted position, each of the tab strips is fed by a pair of rolls 4e, 48

to extend beyond the path of the associated knife corresponding with the desired length of a tab: the leading end of the trip is directed by guide elements 49 into engagement with the tab-coating roll l5. Upon downward movement of the knives to sever the tab strip a tab is cut from 4 arrangement in which the large shallow tray of adhesive needed replenishment as often as eight to twelve times per day.

The space or chamber 38 between the container i6 and an outer container i1 is filled with water maintained, when hot glue is used, at

suitably high temperature by electric heaters it,

or equivalent source of heat, controlled by thermostat l9. A switch, not shown, allows deenergization of the heaters when cold glue is used. Chamber 88 may be drained by opening faucet 38 and re-filled through the opening 31 exposed when the cover member 39 is opened;

the leading end of each strip and the tabs so I formed are carried by roll I! toward roll I onto which they are deflected by the stripper blades buring transport of the tabs by roll l8, their wrapper-engaging faces receive a coating of ad-' hesive which is more viscous, because of its lower temperature and/or the churning received in valley V, than the adhesive applied by roll I to the other or box-engaging faces of the tabs. This difference in viscosity is desirable because quicker setting of the adhesive attaching the tabs to the wrappers minimizes possibility of displacement of the tabs during the application of the tabbed wrappers to boxes at which time the adhesive on the box-engaging face of the wrappers and tabs should be set to substantially lesser degree.

Unlike prior arrangements, such as those of aforesaid Rider Patents 1,857,260 and 2,028,878, my roll I! does not dip below the surface of a large open body of adhesive agitated or stirred by the roll with consequent undesirable production of foam and escape of adhesive-bearing vapors. With the present improved arrangement, the coating of adhesive transferred to roll- I5 is free of blisters, craters and like irregularities due to foam and is of consistency or viscosity not subject to variation because of condensation on the rolls of adhesive-bearing vapors.

The excess of adhesive supplied to valley Vi flows from the ends thereof, through the gaps 14a in the scraper or doctor blade i4, into tray il whose bottom is inclined downwardly and forwardly to an outlet 4! disposed above the funnel or equivalent member 42 for return of the adhesive to a container I! which serves as a reservoir of capacity sufficient for an extended run, for example; of one day or several thousand boxes: this is in contrast with aforesaid priO because the water in chamber 38 is used only for heating and does not come into contact with adhesive it need be replaced only infrequently.

The adhesive within the container I6 is continuously agitated by paddle 20, or equivalent. whose blades slowly rotate below and generally parallel to the surface of the glue to maintain uniformity of it characaeristics, dependent upon composition and temperature, essential to maintenance of high rate of useful production of boxes. With fall in level of the adhesive, each paddle in turn rotates at or immediately above the surface of the adhesive to break any bubbles that may form due to entrapment of air by adhesive falling from tray Ii back into the main body thereof.

The shaft 2| to which the paddle 28 is attached (Figs. 1 and 3) is supported by bearing 22 in the cover member 23 of the container It, I! and is driven from the continuously rotating shaft 24 of mechanism G through the gear 25 and pulley 28 attached to shaft 21, belt 28 and pulley 29 rotatable on shaft II and connected thereto through the friction or slip clutch comprising member 30 attached, as by key 36a for rotation with shaft 2|, and member 3| attached to or integral with pulley 29.

The slip clutch precludes breakage of any of 'the mechanism in event of inadvertent attempt to start the machine when the glue is hard and allows rapid manual operation of the paddles by hand wheel 39 after addition of water or glue thus more quickly to procure uniformity.

In normal use of the machine for applying adhesive to wrappers and tabs, the adhesive flows from the bottom of the tank through pipe 50 to the pump 6|, preferably disposed below the level of the bottom of the tank IS in avoidance of presence of foam in the pumped adhesive, connected by piping I52 to the spray or distributing head I disposed above the upper valley V between the rolls l and 4. The pump 5! may be of simple rotary impeller type having its movable element attached to or driven from shaft 2?. The adhesive not applied to the wrappers and tabs is returned by gravity, as above described, to tank IS in which it is mixed with the main body of the adhesive.

The confinement of the adhesive within closed container l6 and the substantial capacity of the container minimize variations, otherwise occurring during a working day, of the character= istics of the adhesive applied to the Wrap er: and tabs. With prior arrangement, using an open reservoir, it was necessary frequently to add water in replacement of evaporiaation losses. Confinement of the adhesive also prevents its contamination by lint, dust, scraps of paper and other foreign matter. The isolation of the space above the heated adhesive precludes condensation of adhesive-bearing vapors upon the wrappers or tabs or upon the elements of the of water or other cleansing liquid. Preferably,

and necessarily when hot glue has been used, the cleaning iluid is preheated by its passage through coil 55, or equivalent heat-exchange device, disposed within chamber 38.

With the bridge or frame 43 in normal operating position, the water flows along the same paths previously traversed by adhesive and so removes all trace thereof from the rolls, scrapers and associated parts. However, the contaminated cleaning liquid is not, for ordinary cleaning, permitted to flow to the reservoir or inner container 66 but is diverted therefrom to waste. More particularly, as the cleaning liquid falls from. the tray outlet 4l toward the funnel 42 of the inner container 16, it is intercepted by funnel 54a carried by pipe 55a and moved, when the liquid falling toward funnel 42 appears to contain a substantial percentage of water, to position between outlet and funnel 42. The bracket 58 in which pipe 55a. is pivotally mounted ma extend from and form an integral part of the outer container ii. The movable waste pipe 55a is in continuous communication with pipe or hose 51 which discharges the used cleaning liquid to any suitable destination such as, for example, the bucket 5%. Usually not more than a gallon or two oi water is required to obtain thorough cleaning.

To ensure and hasten removal of adhesive from the tab-engaging roll ii, there is provided spray head or pipe 59 which extends between the fram members 35 of the machine in such position that when the tabbing mechanism is in operating position (Fig. 4) Jets of cleaning liquid issuing from the perforations 60 in the pipe 59 are directed into the bight of rolls l3 and IS. The pipes 5 and 59 may be concurrently supplied with cleanslng liquid from coil 55 by opening both valves SI and 12.

With the frame 43 swung to the position shown in Fig. l, valve 8| at this time being closed, the cleaning liquid from pipe 5, after washing off the rolls i, 4, the troughs 6 and chutes 9, is

directly discharged from trough l2 into the tray ll. With the bridge 43 in such position, the aforesaid parts are exposed for still further cleaning if the operator finds that desirable and necessary. That parts otherwise diflicult to clean may be reached by the liquid, there may be provided, for manipulation by the operator, a nozzle 62 attached to flexible hose 68 and adapted by opening of valve 84 to be placed in COIIllIlllIllCfl'. tion with coil 55 or equivalent source. When not in use, the hose 83 may be coiled and held in readily accessible position by clips 65 attached to the outer container l1.

To prevent the cleaning liquid, or diluted adhesive, from dripping onto the bed of the machine. upon the container H, or any of the paddie-driving mechanism, as the tabbing mechanism is moved to or is in the position shown in Fig. 1, there is provided the shallow tray or pan ll detachably secured by thumb screws 61 to the side frames 88 of bridge 43. As more clearly shown in Fig. 4, the tray 68 is of such width, or so disposed, that the lip or forward edge 88 does not, in normal operation of the machine, intercept adhesive falling from the valley VI into the tray II. V

In contrast with the cleaning afiorded by the constructions disclosed in aforesaid patents and more fully described in Letters Patent 1,433,976 to Weightman et al., the present arrangement is far more rapid and thorough with consequent substantial improvement in quantity and quality of the boxes produced.

-To prevent entry of foreign matter such as tab clippings into the adhesive-circulation system, there may be provided the removable screen In for covering the drain opening in the bottom of tray II and the screen member H for covering the opening through which the inner container or reservoir l8 receives fresh supply of adhesive.

For brevity in the appended claims the term sheets" is used generically to comprehend wrappers, labels, tabs, and tabbed wrappers or labels.

What I claim is:

1. Apparatus for applying adhesive to sheets for attachment thereof to' boxes comprising in combination with a sheet-engaging roll, a scraper member extending lengthwise of said roll and therewith defining a valley, means for delivering adhesive to said valley, and means for conducting excess adhesive from said valley comprisingtrough structure consisting of an open channel at least at one end of the valley and at its edges engaging said roll and said scraper member on opposite sides of the valley and along the end faces of said roll and scraper member there to effect a closed passage discharging adhesive below said sheet-engaging roll.

2. Apparatus for applying adhesive to sheets and tabs for attachment thereof to boxes comprising a roll for applying adhesive to the sheets and to one side of each of the tabs, a scraper member extending lengthwise of the rollv and therewith defining a valley, a second roll, a scraper member extending lengthwise thereof and therewith defining a second'valley, means for feeding sheets into engagement with one of said rolls.

means for delivering adhesive to said first-named valley means for directing flow of adhesive from said first-named valley to said second valley. and a roll applying adhesive, delivered from said second valley by said second roll, to the other sides of the tabs.

' 3. Apparatus for applving adhesive to wrappers and tabs comprising a wrapper-enga in roll, a scraper member extending lengthwise thereof to define between them a valley. a tabengaeing roll adjacent said first roll for transfer thereto of tabs. a roll for transferring adhesive to said tab-en aging roll. a scraper member extending lengthwise of said transfer roll therewith to define a second valley lower than the first-named valley. means for delivering liquid adhesive to said first valley for application to the box-engaging faces of the wrappers and tabs, and means providing for application of more viscous adhesive to the wrapper-engaging faces of the tabs comprising means for directing flow of excess adhesive from said upper valley to said lower valley.

4. Apparatus for applying adhesive to sheets for attachment thereof to boxes comprising rolls disposed one above another. a scraper member extending lengthwise of each of said rolls and therewith defining a valley, means for delivering 7 liquid adhesive to one of said valleys for application to one face of the sheets, and means providing for application of more viscous adhesive,-

received in a lower of said valleys from said one of said valleys, to the other face of said sheets comprising structure for collecting adhesive from an upper of said valleys and directing it intoia lower of said valleys.

5. Apparatus for applying adhesive to wrappers and tabs comprising a wrapper-engaging roll, a scraper member extending lengthwise thereof and therewith defining a valley, means for directing flow of excess adhesive from the ends of said valley comprising trough structure, a tab-engaging roll, a roll for transferring adhesive to said tab-engaging roll, a second scraper member extending lengthwise of said transfer roll and therewith defining a second valley, and a frame supporting said second scraper member and said transfer and tab-engaging rolls for movement toward and from position in which adhesive from saiditrough structure flows into said second valley.

6. Apparatus for applying adhesive to wrappers and tabs comprising a wrapper-engaging roll, a scraper member extending lengthwise thereof and therewith defining a valley, means for directing flow of excess adhesive from the ends of said valley comprising trough structure, a tab-engaging roll, a roll for transferring ad-- hesive to said tab-engaging roll, a second scraper member extending lengthwise of said transfer roll and therewith defining a second valley, a frame supporting said second scraper member and said transfer and tab-engaging rolls for movement toward and from position in which adhesive from said trough structure flows into said second valley, and a tray for receiving adhesive from said second valley when said movable frame is in aforesaid position and for receiving adhesive from said trough when said frame is away from said position.

7. Apparatus for applying adhesive to wrap- I pers and tabs comprising a wrapper-engaging roll, tabbing mechanism including a tab-engaging roll, a supply of adhesive, means for heating the adhesive, a reservoir for heated adhesive substantially closed and so arranged relative to said mechanism and said rolls that vapors from the heated adhesive within the reservoir will not reach and condense upon said mechanism and said rolls,

and means effecting circulation of adhesive in a path including said rolls and said reservoir.

8, Apparatus for applying adhesive to sheets for attachment thereof to boxes comprising rolls disposed one above another, a scraper member extending lengthwise of each of said rolls therewith to define a valley, a reservoir for adhesive,

means for withdrawing adhesive from said reser-.'

voir and delivering it to a higher of said valleys, means for directing flow 'of excess adhesive from the higher valley to a lower valley, and tray structure for receiving adhesive from the lower valley ply system including a pump forwithdrawing adhesive from said reservoir and delivering it to saidvalley, and means for removing adhesive at least from said roll, said member and said pump comprising means for introducing cleaning liquid into said system in advance of said pump and in substitution for adhesive, and means for intercepting and diverting the cleaning liquid as it falls from said tray toward said opening in said reservoir.

10. :Apparatus for applying adhesive to wrappers and tabs comprising, in combination with a wrapper-engagingroll and a tab-engaging roll, a roll for transferring adhesive to said tab-engaging roll, a liquid distribution system comprising a pump, a discharge pipe extending therefrom to said wrapper-engaging roll, structure directing excess of liquid from said wrapper-engaging roll to said transfer roll, a reservoir containing adhesive and having an opening to receive adhesive, a tray for collecting unused adhesive from which it falls into said opening, a spray-head for directing jets of cleaning liquid into' the bight of said transfer roll and said tab-engaging roll, means operable selectively to su ply adhesive or cleansing liquid to said liquid-distribution system,

means to supply cleansing liquid to said sprayhead, and means for intercepting and diverting the cleansing liquid as it falls from said tray toward said opening in said reservoir.

11. Apparatus for applying adhesive comprising an inner container for adhesive, an outer container cooperating with said inner container to define a chamber for hot fluid, a heat-exchange device disposed in said chamber and traversed by cleansing liquid, an adhesive-applying member, a liquid-distribution system including a pump and a discharge-connection therefrom for supplying liquid to said member, and valve means for selectively connecting the intake of said pump to said inner chamber or to said heat-exchange device.

12. Apparatus for applying adhesive to sheets comprising, in combination with sheet-coating mechanism including a sheet-engaging roll, means for supplying adhesive to said roll, a reservoir for adhesive, means effecting flow of adhesive in a path including said mechanism and said reservoir, means for supplying cleansing liquid, means for heating saidliquid. means for disconnecting said second-named means from said reservoir and connecting it with said liquid supplying means f or withdrawing liquid therefrom through the first-named means, and a connection from the discharge of said first-named means for delivering cleansing liquid to said sheet-coating means for supplying adhesive to said roll, a reservoir for heated adhesive substantially closed and so arranged relative to said mechanism and said rolls that vapors from the heated adhesive within the reservoir will not reach and condense upon said mechanism and said rolls, means effecting flow of adhesive in a path including said mechanism and said reservoir, means for supplying cleansing liquid, means for heating said liquid, means for disconnecting said second-named means from said reservoir and connecting it with said liquid supplying means for withdrawing liquid therefrom through the first-named means. and a connection from the discharge of said firstnamed means for delivering cleansing liquid to said sheet-coating mechanism.

14. Apparatus for applying adhesive to sheets comprising, in combination with sheet-boating -mechanism including a sheet-engaging roll,

means for supplying adhesive to said roll, a reservoi for adhesive, means effecting flow of adhesive in a path including said mechanism and said reservoir, means for supplying cleansing liquid, means for heating said liquid, means for disconnecting said second-named means from said reservoirand connecting it with said liquid supplying means for withdrawing liquid therefrom through said second-named means, a connection from the discharge of said second-named means for delivering cleansing liquid to said sheet-coating mechanism, and means for returning adhesive-containing liquid from said mechanism into said reservoir.

15. Apparatus for applying. adhesive to sheets comprising, in combination with sheet-coating mechanism including a sheet-engaging roll, means for supplying adhesive to said roll, a reservoir for adhesive, means effecting flow of adhesive in a path including said mechanism and said reservoir, means for supplying cleansing liquid, means for heating said liquid, means for disconnecting said second-named means from said reservoir and connecting it with said liquid supplying means for withdrawing liquid therefrom through said second-named means, a. connection from the discharge of said second-named means for delivering cleansing liquid to said sheet-coating mechanism, and means for returning liquid after application thereof to said sheet-coatin mechanism either to said reservoir or to a receptacle independent of said reservoir.

16. Apparatus for applying adhesive to sheets comprising, in combination with sheet-coating mechanism including a sheet-engaging roll, means for supplying adhesive to said roll, a reservoir for adhesive, a pump effecting flow of adhesive in a path including said mechanism and said reservoir. means for supplying cleansing liquid, means for heating said liquid, means for disconnecting said pump from said reservoir and connecting it with said liquid supplying means for withdrawing liquid therefrom through the pump, a connection from the discharge of said pump for delivering cleansing liquid to said sheetcoating mechanism, and means directly connecting said liquid supplying means, in a path excluding said pump, to said sheet-coating mechanism for applying cleansing liquid thereto.

WALTER '1'. 3m 

